Atrioventricular nodal re-entry tachycardia is a common supraventricular arrhythmia. The rate of recurrence is relatively high, and accordingly ablative therapy became the first-line suggested therapy. In this review, we highlight the electrocardiographic clues to the diagnosis of atrioventricular nodal re-entry tachycardia, also we present the electrophysiological data and maneuvers that enable the ruling out of other supraventricular tachycardias and ensure an accurate and specific diagnosis of atrioventricular nodal reentrant tachycardia.